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The prompt gamma neutron activation analysis (PGNAA) facility at the Pakistan Research Reactor (PARR-I) has been used for elemental analysis of different kinds of materials. A high-efficiency, high-resolution gamma spectrometer based on a high-purity germanium detector is being employed in this study. The cadmium ratio of the incident neutron beam is 62 and the thermal neutron flux at the target position is about 1.5 × 106 n/cm²/s. The system is usually operated in Compton suppression mode to enhance peak to background ratio in the lower energy region (< 1.5 MeV). The gamma ray detector is calibrated with standard radioactive sources up to 1.5 MeV. The aim of the present study is to determine the quantity of boron in reactor grade steels as well as in some other materials containing boron. The results of boron assessment in SS-304L and amorphous (Fe0.99Mo0.01)78Sid9B13 alloy are also presented. [ABSTRACT FROM AUTHOR]

Abstract: Potassium content in tea brew was determined by gamma-ray spectroscopy, using the 1461keV gamma-ray from 40K, the naturally occurring radioactive isotope of potassium. We measured radiation with a shielded HPGe detector from individual test samples of tea leaves, before and after infusion preparation, and from commercial instant tea powder. The correction factor for the gamma-ray self-absorption in the extended source was determined with the help of Monte-Carlo simulations. This gamma-ray spectroscopy technique enabled the absolute determination of potassium content with a relative uncertainty smaller than 4%, at the one standard deviation confidence level, showing the feasibility of this method. An experiment to evaluate a possible systematic uncertainty due to K distribution heterogeneity in the sample was performed, with the result that the corresponding relative standard deviation is smaller than 2% at 95% confidence level. [Copyright &y& Elsevier]